Assuming 100% dissociation, calculate the freezing point and boiling point of 2.91 m sncl4(aq. constants may be found here.

The formula to calculate depression of the freezing point is:

ΔTf = i * Kf * m

Were i is VanHoff constant, which counts for the dissociation factor. In this case, given the 100% dissociation of the molecule, 1 mol of SnCl4 produces 5 ions: 1 of Sn (4+) and 4 of Cl(1-), then i = 5.

Kf is the cryoscopic constant of the solvent: 1.86°C/m for water, and

m is the molality of the solution: 2.91 m

=> ΔTf = 5 * 1.86°C/m * 2.91 m = 27.063°C.

And the freezing point of the water will be its normal freezing point less 26.063°C => Tf = 0°C - 27.063 °C = - 27.063°C.

- 27.1 °C